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          为什么这样的数据t检验后p值会很小的？
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             为什么这样的数据t检验后p值会很小的？
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               2014年6月12日 上午2:47
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              <p>
               第二列为0的是一个样本，为1的是另一个，
               <br/>
               用t检验p值小于0.05，
               <br/>
               但是画直方图，两个根本是同一个分布，
               <br/>
               求问这是咋回事？
              </p>
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               2014年6月17日 上午9:03
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              <pre class="highlight ">a &lt;- matrix(c(0.57002,1        ,
            40.56,1          ,
            7.8499,1         ,
            -36.91,1         ,
            -45.15,1         ,
            6.2401,1         ,
            4.79,1           ,
            1.0899,1         ,
            -9.44,1          ,
            6.54,1           ,
            -0.89008,1       ,
            -0.40994,1       ,
            51.63,1          ,
            -27.76,1         ,
            4.03,1           ,
            -31.86,1         ,
            13.14,1          ,
            14.37,1          ,
            0.029999,1       ,
            -5.54,1          ,
            0.029953,1       ,
            -7.6901,1        ,
            5.4001,1         ,
            10.49,1          ,
            -8.04,1          ,
            -4.51,1          ,
            13.97,1          ,
            12.53,1          ,
            5.22,1           ,
            55.93,1          ,
            -11.22,1         ,
            14.22,1          ,
            5.64,1           ,
            -19.3,1          ,
            -32.31,1         ,
            2.6,1            ,
            7.29,1           ,
            7.4401,1         ,
            -18.49,1         ,
            13.94,1          ,
            4.04,1           ,
            52.62,1          ,
            -9.86,1          ,
            31.46,1          ,
            3.2099,1         ,
            3.73,1           ,
            -3.4,1           ,
            8.76,1           ,
            -13.23,1         ,
            -3.0899,1        ,
            -4.9599,1        ,
            -18.34,1         ,
            -9.77,1          ,
            -4.6801,1        ,
            6.1901,1         ,
            0.63007,1        ,
            19.79,1          ,
            11.74,1          ,
            19.33,1          ,
            19.15,1          ,
            -18.1,1          ,
            9.98,1           ,
            -12.29,1         ,
            -0.25995,1       ,
            -9.1901,1        ,
            11.15,1          ,
            -34.51,1         ,
            -11.59,1         ,
            -27.59,1         ,
            4.01,1           ,
            -6.3199,1        ,
            1.3699,1         ,
            -0.26001,1       ,
            -15.23,1         ,
            -0.019989,1      ,
            26.03,1          ,
            17.03,1          ,
            -5.53,1          ,
            0.52005,1        ,
            4.7,1            ,
            -7.88,1          ,
            8.24,1           ,
            -4.9299,1        ,
            -2.07,1          ,
            40.99,1          ,
            21.11,1          ,
            -1.5099,1        ,
            -17.84,1         ,
            -9.6501,1        ,
            -4.89,1          ,
            41.97,1          ,
            -24.97,1         ,
            -47.3,1          ,
            -0.93008,1       ,
            -24.87,1         ,
            -2.3601,1        ,
            -8.4401,1        ,
            -14.77,0         ,
            -17.44,0         ,
            -7.21,0          ,
            -2.88,0          ,
            -22.5,0          ,
            2.52,0           ,
            1.7501,0         ,
            -31.26,0         ,
            -7.35,0          ,
            -1.01,0          ,
            -52.98,0         ,
            8.76,0           ,
            25.49,0          ,
            3.17,0           ,
            -11.82,0         ,
            -14.19,0         ,
            -11.5,0          ,
            -36.15,0         ,
            52.53,0          ,
            -6.1801,0        ,
            -42.32,0         ,
            -31.83,0         ,
            12.57,0          ,
            -3.6499,0        ,
            -0.14996,0       ,
            -5.89,0          ,
            -2.4001,0        ,
            -3.62,0          ,
            -4.38,0          ,
            -23.12,0         ,
            -11.56,0         ,
            -19.25,0         ,
            47.1,0           ,
            -20.03,0         ,
            3.25,0           ,
            3.9301,0         ,
            -10.02,0         ,
            -3.0299,0        ,
            -0.91005,0       ,
            -13.14,0         ,
            22.4,0           ,
            -42.83,0         ,
            -16.93,0         ,
            -13.3,0          ,
            -46.04,0         ,
            -18.76,0         ,
            -10.35,0         ,
            -4.57,0          ,
            -4,0             ,
            30.42,0          ,
            14.13,0          ,
            -45.71,0         ,
            -1.24,0          ,
            -5.71,0          ,
            -43.42,0         ,
            19.02,0          ,
            -17.34,0         ,
            1.7801,0         ,
            -4.67,0          ,
            -10.11,0         ,
            -14.48,0         ,
            2.9,0            ,
            -15.15,0         ,
            42.03,0          ,
            7.31,0           ,
            -2.3499,0        ,
            -7.08,0          ,
            10.08,0          ,
            11.01,0          ,
            1.76,0           ,
            0.9899,0         ,
            -8.89,0          ,
            5.38,0           ,
            -23.42,0         ,
            -4.12,0          ,
            -36.98,0         ,
            -4.99,0          ,
            -4.9501,0        ,
            -3.8399,0        ,
            -17.52,0         ,
            -7.35,0          ,
            -1.04,0          ,
            -12.09,0         ,
            -23.92,0         ,
            6.8499,0         ,
            -3.97,0          ,
            42.43,0          ,
            -20.52,0         ,
            -14.3,0          ,
            -15.94,0         ,
            -0.95001,0       ,
            -37.38,0         ,
            -14.36,0         ,
            14.97,0          ,
            -6.23,0          ,
            39.93,0          ,
            -65.34,0         ,
            -27.15,0         ,
            -4,0             ,
            -10.05,0         ,
            26.67,0          ,
            -9.9199,0        ,
            12.66,0          ,
            19.83,0          ,
            -44.88,0         ,
            3.2799,0         ,
            -10.04,0         ,
            -30.55,0         ,
            -13.25,0         ,
            -8,0             ,
            -3.4199,0        ,
            -6.8201,0        ,
            4.8102,0         ,
            -8.9901,0        ,
            -21.77,0         ,
            -5.92,0          ,
            13.68,0          ,
            11.1,0           ,
            -0.74997,0       ,
            2.49,0           ,
            -4.98,0          ,
            -3.2399,0        ,
            -24.91,0         ,
            12.24,0          ,
            11.01,0          ,
            10.66,0          ,
            -1.11,0          ,
            -67.97,0         ,
            -9.48,0          ,
            11.76,0          ,
            34.64,0          ,
            0.55008,0        ,
            -5.89,0          ,
            -10.19,0         ,
            -11.82,0         ,
            -4.97,0          ,
            -4.6501,0        ,
            12.61,0          ,
            -10.48,0         ,
            7.4499,0         ,
            -16.77,0         ,
            -0.75005,0       ,
            10.02,0          ,
            -7.41,0          ,
            -16.11,0         ,
            -21.22,0         ,
            -12.08,0         ,
            -8.1,0           ,
            -22.82,0         ,
            32.078,0         ,
            2.17,0           ,
            -13.95,0         ,
            2.02,0           ,
            -7.1201,0        ,
            -73.18,0         ,
            -12.8,0          ,
            -3.09,0          ,
            8.7801,0         ,
            30.21,0          ,
            -24.06,0         ,
            -48.98,0         ,
            0.82004,0        ,
            -15.36,0         ,
            -6.9,0           ,
            -14.56,0         ,
            53.73,0          ,
            -38.96,0         ,
            -7.36,0          ,
            -38.24,0         ,
            -10.7,0          ,
            42.76,0          ,
            -11.51,0         ,
            -1.44,0          ,
            28.67,0          ,
            -10.37,0         ,
            -11.73,0         ,
            -5.9801,0        ,
            -0.67998,0       ,
            2.3499,0         ,
            -24.25,0         ,
            -25.01,0         ,
            6.06,0           ,
            0.51004,0        ,
            4.74,0           ,
            -2.9399,0        ,
            -28.58,0         ,
            -44.01,0         ,
            -69.09,0         ,
            -3.1,0           ,
            12.81,0          ,
            -10.6,0          ,
            -5.2501,0        ,
            15.41,0          ,
            -61.07,0         ), ncol=2, byrow=TRUE)
x &lt;- a[a[,2]==0, 1]
y &lt;- a[a[,2]==1, 1]
plot(density(x))
lines(density(y))
t.test(x,y)
</pre>
              <p>
              </p>
              <p>
               我试了一下，从图片上看两组的分布是有区别的，均值看上去不一样
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               2014年6月17日 下午1:12
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               3 楼
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               一个样本是来自于正态分布，另一个来自于二项分布，做t检验合适吗？
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